Present inventions related to ladder guards and particularly to guard elements secured to the upper end of the side rails of a ladder for mounting against the vertical support wall for minimizing of any damage to such support walls.
Ladders are widely used for working on above the ground levels. A widely used ladder includes a pair of side rails interconnected by longitudinally spaced steps or rungs which extend between and are firmly affixed to the side rails. The upper end of the side rails will project upwardly from the uppermost rung or step a short distance and provide for interengagement to a vertical support. The bottom end of the side rails more suitably constructed to rest on the ground or floor area for supporting of the ladder at an appropriately inclined position against the vertical support. Various prior art pad-type devices have been suggested to be attached to the upper ends of the side rails for purposes of protecting a vertical wall from damage as a result of engagement by the rigid side rails and also to improve the stability of the ladder on the support structure. For example, U.S. Pat. No. 138,171 which issued Nov. 29, 1938, for an anti-slip device discloses cupped elements formed of a rubber like material which are fitted over the upper end of the ladder siderail. The rubber-like material is formed with extended portions to distribute the applied pressure or force of the ladder over a somewhat larger area and also stabilizes the inter-connection by providing a greater frictional engagement with the wall. The patent also provides for roughening of the wall engaging portion to increase the friction forces. As disclosed in that patent, cupped element has its socket formed to closely fit over the ladder to secure the element in place.
Various other similar devices have been suggested in the prior art. U.S. Pat. No. 2,925,877 which issued Feb. 23, 1964 discloses a similar element having an enlarged bumper portion projecting laterally outwardly from the body portion and having a planar surface adapted to engage the vertical wall. The vertical wall engaging surface is provided with a plurality of parallel longitudinal grooves. A somewhat similar pad like structure is shown in U.S. Pat. No. 3,929,208 which issued Dec. 30, 1975, for a "Ladder Bearing Plate" in which a cap member is provided with a screw like attachment to the upper end of the ladder and with an outer flat pad for abutting the wall surface. More recently, a rubber cap member has been proposed in which the outer upper end is curved to conform to the curved ladder ends widely used in present day ladder structures. The element is formed of a rubber like material with corrugate end wall extending completely around the guard the end walls is integral with flat sidewalls for attachment to the upper end of the ladder.
End guards also protect the ends of the ladder from accumulated water as well as nicks, scratches, gouges on the ends which otherwise are often encountered during the use of the ladder.
Although the prior art provides satisfactory devices for protecting the wall and promote stabilization of the ladder on the wall, none of the devices appear to provide an optimum type of a support at a minimum cost, with most efficient and low cost production and wherein the portion of the ladder engaging the wall provides maximum surface engagement for maximizing stability of the ladder.